San Antonio Express -- In high school, Christopher Baltazar favored getting dirty and sweaty in the field over the spit-and-polish look that Junior ROTC students push themselves to achieve.

So it wasn’t a surprise to any of his friends that he joined the Marines after graduating last year from Judson High School.

The Judson community now is reeling over the news from Afghanistan. His family learned late Thursday that he died after stepping on a pressure-activated explosive.

Retired Air Force Lt. Col. James Grace, senior aerospace science instructor at Judson, remembered Baltazar, 19, as a quiet, respectful young man who seemed more comfortable in camouflage than a military dress uniform.

Using a compass and map, Baltazar and his JROTC orienteering team from Judson would compete against other schools in timed land-navigation drills at Camp Bullis. They would run virtually the whole time through a rugged course extending at least a mile or two, Grace said.

“He was more into the idea of getting out there and being a hardcore military guy,” he said.

Judson officials decided to honor Baltazar with a moment of silence at Friday night’s football game against Smithson Valley.

Baltazar is the third San Antonian killed in Afghanistan in less than a month. Marine Lance Cpl. Travis Babine, who died Aug. 6 in Farah province, and Army Staff Sgt. Clayton P. Bowen, who died Aug. 18 in Paktika province, also were killed by improvised explosives.

Brendon Baltazar told his brother he loved him the last time the young Marine called on his satellite phone from Afghanistan, about two weeks ago. Having been raised by a mother who had deployed several times, including once to Iraq, the two had a habit of saying “I love you” each time they spoke.

“In a military family, you just don’t want to send anyone away without hearing that,” said Baltazar, 18.

Christopher Shawn Baltazar Jr. would’ve turned 20 on Sept. 23. He was strong-willed, like his mother, Army Staff Sgt. Beatriz Alberts, who works at Walter Reed Army Medical Center in Washington, his brother said.

But he also had a sense of humor that came naturally. He listed “Scrubs” as his favorite television show on his MySpace page. “Dogs, snakes and Marines” were his animals of choice.

“There’s never been anyone else on this planet who I could not be angry at,” his brother said. “If he poked me with a stick, I’d curse at him, and laugh at him at the same time.”

Baltazar also had a sister and two stepbrothers, his brother said.

Will Weber, 19, said Baltazar was one of his closest friends growing up. They shared boyhood adventures, riding bikes and playing football and baseball together in the Sunrise neighborhood on the Northeast Side.

Baltazar, a native of New York state, was new to San Antonio when they met in sixth grade. They later were in the youth group together at Cornerstone Church, Weber said.

“He was always a real funny, joyful, happy person,” he said. “He was so excited about being a Marine. He believed in honor and serving his country.”

Arrangements are pending for a local funeral and burial at Fort Sam Houston National Cemetery.